The game again saw Gundogan face boos from large sections of the home crowd after coming on as a substitute during the second half.

Some Germany fans clearly remain unimpressed over his decision to pose for a photo with Turkish president Recep Tayyip Erdogan during a visit to London last month, along with Arsenal's Mesut Ozil - who also has Turkish heritage - and Everton's Turkey forward Cenk Tosun.

Gundogan handed over a City shirt with the message "to my president, with my respects," which led to criticism, including from politicians and DFB (German Football Association) chief Reinhard Grindel.

Low turned to the home fans trying to encourage support for Gundogan when he sent the midfielder on in the 57th minute.

Gundogan, though, was soon jeered when seeing two close-range efforts saved not long after taking to the pitch.

The Germany head coach addressed the issue head-on during a post-match interview with German broadcaster ARD1.

Low called for unity as his squad prepare to jet out to Russia ahead of their tournament opener against Mexico in Moscow on June 17.

"First of all, having a national player booed like that helps nobody. I ask you this - what should Ilkay do now?" Low said. "He took a picture, yes, but he made no political statement.

"He spoke about this with the press last week and underlined his support for German values, that he was born here, brought up here, his family and friends are here. Everybody must move on from this now."

Low had taken no chances with the fitness of Ozil, who sat out Friday night's match as a precaution because of a left knee problem.

It was, though, at least an improved performance following the loss to Austria in Klagenfurt.

"We will continue to improve and, when the tournament starts, we will be ready," Low said, quoted on www.dfb.de.

"I believe we started well. Our movement was good in the first half. In the second half, we rested on our laurels a bit.

"We missed too many chances and gave too many away. At the end, we even needed a bit of luck.

"Next week, we will go out with a more dynamic and vibrant performance."